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* USB: core: Fix bug caused by duplicate interface PM usage counterAlan Stern2019-04-191-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The syzkaller fuzzer reported a bug in the USB hub driver which turned out to be caused by a negative runtime-PM usage counter. This allowed a hub to be runtime suspended at a time when the driver did not expect it. The symptom is a WARNING issued because the hub's status URB is submitted while it is already active: URB 0000000031fb463e submitted while active WARNING: CPU: 0 PID: 2917 at drivers/usb/core/urb.c:363 The negative runtime-PM usage count was caused by an unfortunate design decision made when runtime PM was first implemented for USB. At that time, USB class drivers were allowed to unbind from their interfaces without balancing the usage counter (i.e., leaving it with a positive count). The core code would take care of setting the counter back to 0 before allowing another driver to bind to the interface. Later on when runtime PM was implemented for the entire kernel, the opposite decision was made: Drivers were required to balance their runtime-PM get and put calls. In order to maintain backward compatibility, however, the USB subsystem adapted to the new implementation by keeping an independent usage counter for each interface and using it to automatically adjust the normal usage counter back to 0 whenever a driver was unbound. This approach involves duplicating information, but what is worse, it doesn't work properly in cases where a USB class driver delays decrementing the usage counter until after the driver's disconnect() routine has returned and the counter has been adjusted back to 0. Doing so would cause the usage counter to become negative. There's even a warning about this in the USB power management documentation! As it happens, this is exactly what the hub driver does. The kick_hub_wq() routine increments the runtime-PM usage counter, and the corresponding decrement is carried out by hub_event() in the context of the hub_wq work-queue thread. This work routine may sometimes run after the driver has been unbound from its interface, and when it does it causes the usage counter to go negative. It is not possible for hub_disconnect() to wait for a pending hub_event() call to finish, because hub_disconnect() is called with the device lock held and hub_event() acquires that lock. The only feasible fix is to reverse the original design decision: remove the duplicate interface-specific usage counter and require USB drivers to balance their runtime PM gets and puts. As far as I know, all existing drivers currently do this. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-and-tested-by: syzbot+7634edaea4d0b341c625@syzkaller.appspotmail.com CC: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* usb: typec: Improve Alt Mode documentationHeikki Krogerus2018-12-193-12/+14
| | | | | | | | | Adding the document to the usb index file and fixing a few references. Also, exposing the code examples as "literal blocks" so they are more easy to read. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* usb: typec: Bus type for alternate modesHeikki Krogerus2018-07-021-0/+136
| | | | | | | | | | Introducing a simple bus for the alternate modes. Bus allows binding drivers to the discovered alternate modes the partners support. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Tested-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'usb-for-v4.18' of ↵Greg Kroah-Hartman2018-05-241-2/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next usb: changes for v4.18 merge window A total of 98 non-merge commits, the biggest part being in dwc3 this time around with a large refactoring of dwc3's transfer handling code. We also have a new driver for Aspeed virtual hub controller. Apart from that, just a list of miscellaneous fixes all over the place.
| * usb: dwc3: gadget: remove duplicated missed isoc handlingFelipe Balbi2018-05-211-1/+0
| | | | | | | | | | | | | | Now, this part of the code is duplicated and brings no extra value to the driver. Let's remove it. Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
| * usb: dwc3: gadget: remove DWC3_EP_BUSY flagFelipe Balbi2018-05-211-1/+1
| | | | | | | | | | | | It has no use anymore. Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
* | Documentation: typec.rst: Use literal-block element with ascii artHeikki Krogerus2018-04-221-1/+1
|/ | | | | | | | | | | | | | Using reStructuredText literal-block element with ascii-art. That prevents the ascii art from being processed as reStructuredText. Reported-by: Masanari Iida <standby24x7@gmail.com> Fixes: bdecb33af34f ("usb: typec: API for controlling USB Type-C Multiplexers") Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Tested-by: Jani Nikula <jani.nikula@intel.com> Reported-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'usb-4.17-rc1' of ↵Linus Torvalds2018-04-051-11/+62
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB/PHY updates from Greg KH: "Here is the big set of USB and PHY driver patches for 4.17-rc1. Lots of USB typeC work happened this round, with code moving from the staging directory into the "real" part of the kernel, as well as new infrastructure being added to be able to handle the different types of "roles" that typeC requires. There is also the normal huge set of USB gadget controller and driver updates, along with XHCI changes, and a raft of other tiny fixes all over the USB tree. And the PHY driver updates are merged in here as well as they interacted with the USB drivers in some places. All of these have been in linux-next for a while with no reported issues" * tag 'usb-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (250 commits) Revert "USB: serial: ftdi_sio: add Id for Physik Instrumente E-870" usb: musb: gadget: misplaced out of bounds check usb: chipidea: imx: Fix ULPI on imx53 usb: chipidea: imx: Cleanup ci_hdrc_imx_platform_flag usb: chipidea: usbmisc: small clean up usb: chipidea: usbmisc: evdo can be set e/o reset usb: chipidea: usbmisc: evdo is only specific to OTG port USB: serial: ftdi_sio: add Id for Physik Instrumente E-870 usb: dwc3: gadget: never call ->complete() from ->ep_queue() usb: gadget: udc: core: update usb_ep_queue() documentation usb: host: Remove the deprecated ATH79 USB host config options usb: roles: Fix return value check in intel_xhci_usb_probe() USB: gadget: f_midi: fixing a possible double-free in f_midi usb: core: Add USB_QUIRK_DELAY_CTRL_MSG to usbcore quirks usb: core: Copy parameter string correctly and remove superfluous null check USB: announce bcdDevice as well as idVendor, idProduct. USB:fix USB3 devices behind USB3 hubs not resuming at hibernate thaw usb: hub: Reduce warning to notice on power loss USB: serial: ftdi_sio: add support for Harman FirmwareHubEmulator USB: serial: cp210x: add ELDAT Easywave RX09 id ...
| * usb: typec: API for controlling USB Type-C MultiplexersHeikki Krogerus2018-03-221-11/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | USB Type-C connectors consist of various muxes and switches that route the pins on the connector to the right locations. The USB Type-C drivers need to be able to control the muxes, as they are the ones that know things like the cable plug orientation, and the current mode that was negotiated with the partner. This introduces a small API for registering and controlling cable plug orientation switches, and separate small API for registering and controlling pin multiplexer/demultiplexer switches that are needed with Accessory/Alternate Modes. Reviewed-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | usb: musb: remove blackfin portArnd Bergmann2018-03-261-3/+0
|/ | | | | | | | | | | | The blackfin architecture is getting removed, so we can clean up all the special cases in the musb driver. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Aaron Wu <aaron.wu@analog.com> Acked-by: Bin Liu <b-liu@ti.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> [arnd: adding in fixups from Aaron and Stephen] Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* usb: doc: Update document for USB3 debug port usageLu Baolu2017-12-211-0/+52
| | | | | | | | | | | Update Documentation/driver-api/usb/usb3-debug-port.rst. This update includes the guide for using xHCI debug capability based TTY serial link. Cc: Mathias Nyman <mathias.nyman@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* Documentation/driver-api/usb: Replace dead linkStefan Tatschner2017-12-111-1/+1
| | | | | | | | | | | | | | This link is dead: $ curl -vI http://usb.cs.tum.edu/usbdoc * Could not resolve host: usb.cs.tum.edu * Closing connection 0 curl: (6) Could not resolve host: usb.cs.tum.edu I found the document somewhere else. Let's replace it. Signed-off-by: Stefan Tatschner <stefan.tatschner@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* Documentation: fix usb related doc refsTom Saeger2017-10-121-3/+1
| | | | | | | Update ref to usb proc_usb_info.txt. Signed-off-by: Tom Saeger <tom.saeger@oracle.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* Merge tag 'usb-for-v4.13' of ↵Greg Kroah-Hartman2017-06-204-0/+997
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-testing Felipe writes: usb: changes for v4.13 merge window This time around we have a total of 57 non-merge commits. A list of most important changes follows: - Improvements to dwc3 tracing interface - Initial dual-role support for dwc3 - Improvements to how we handle DMA resources in dwc3 - A new f_uac1 implementation which much more flexible - Removal of AVR32 bits - Improvements to f_mass_storage driver
| * usb: move ReST documentation to Documentation/driver-api/usb/Felipe Balbi2017-06-023-0/+286
| | | | | | | | | | | | This is where all other USB ReST documentation has moved to. Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
| * usb: dwc3: add ReST documentationFelipe Balbi2017-06-022-0/+713
|/ | | | | | | Document a few details about DWC3 in order to help people report bugs and debug DWC3. Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
* usb.rst: move documentation from proc_usb_info.txt to USB ReST bookMauro Carvalho Chehab2017-04-201-34/+405
| | | | | | | | | | | | | The contents of proc_usb_info.txt complements what's there at driver-api usb book. Yet, it is outdated, as it still refers to the USB character devices as usbfs. So, move the contents to usb.rst, adjusting it to point to the right places. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* docs-rst: usb: update old usbfs-related documentationMauro Carvalho Chehab2017-04-201-120/+60
| | | | | | | | | | | | There's no usbfs anymore. The old features are now either exported to /dev/bus/usb or via debugfs. Update documentation accordingly, pointing to the new places where the character devices and usb/devices are now placed. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* docs-rst: fix usb cross-referencesMauro Carvalho Chehab2017-04-116-5/+11
| | | | | | | | | As some USB documentation files got moved, adjust their cross-references to their new place. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb.rst: get rid of some Sphinx errorsMauro Carvalho Chehab2017-04-111-3/+3
| | | | | | | | | | | | | Get rid of those warnings: Documentation/driver-api/usb/usb.rst:615: ERROR: Unknown target name: "usb_type". Documentation/driver-api/usb/usb.rst:615: ERROR: Unknown target name: "usb_dir". Documentation/driver-api/usb/usb.rst:615: ERROR: Unknown target name: "usb_recip". Documentation/driver-api/usb/usb.rst:679: ERROR: Unknown target name: "usbdevfs_urb_type". Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb/URB.txt: convert to ReST and update itMauro Carvalho Chehab2017-04-113-0/+291
| | | | | | | | | | | | | | | | | The URB doc describes the Kernel mechanism that do USB transfers. While the functions are already described at urb.h, there are a number of concepts and theory that are important for USB driver developers. Convert it to ReST and use C ref links to point to the places at usb.h where each function and struct is located. A few of those descriptions were incomplete. While here, update to reflect the current API status. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb/persist.txt: convert to ReST and add to driver-api bookMauro Carvalho Chehab2017-04-112-0/+170
| | | | | | | | | This document describe some USB core features. Add it to the driver-api book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb/hotplug.txt: convert to ReST and add to driver-api bookMauro Carvalho Chehab2017-04-112-0/+155
| | | | | | | | | This document describe some USB core features. Add it to the driver-api book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* error-codes.rst: convert to ReST and add to driver-api bookMauro Carvalho Chehab2017-04-112-0/+206
| | | | | | | | | This document describe some USB core features. Add it to the driver-api book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb/dma.txt: convert to ReST and add to driver-api bookMauro Carvalho Chehab2017-04-112-0/+137
| | | | | | | | | This document describe some USB core features. Add it to the driver-api book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb/power-management.txt: convert to ReST and add to driver-api bookMauro Carvalho Chehab2017-04-112-0/+795
| | | | | | | | | This document describe some USB core functions. Add it to the driver-api book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb/callbacks.txt: convert to ReST and add to driver-api bookMauro Carvalho Chehab2017-04-112-0/+158
| | | | | | | | | This document describe some USB core functions. Add it to the driver-api book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb/bulk-streams.txt: convert to ReST and add to driver-api bookMauro Carvalho Chehab2017-04-112-0/+84
| | | | | | | | | This document describe some USB core functions. Add it to the driver-api book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb/anchors.txt: convert to ReST and add to driver-api bookMauro Carvalho Chehab2017-04-112-0/+84
| | | | | | | | | This document describe some USB core functions. Add it to the driver-api book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* writing_musb_glue_layer.rst: Enrich its ReST representationMauro Carvalho Chehab2017-04-111-315/+301
| | | | | | | | | | | | | | | | | | | | | | | This file is actually quite complex, and required several manual handwork: - add a title for the document; - use the right tags for monospaced fonts; - use c references where needed; - adjust cross-reference to writing_usb_driver.rst - hightlight cross-referenced lines. With regards to C code snippet line highlights, the better would be to use :linenos: for the C code snippets that are referenced by the line number. However, at least with Sphinx 1.4.9, enabling it cause the line number to be misaligned with the code, making it even more confusing. So, instead, let's use :emphasize-lines: tag to mark the lines that are referenced at the text. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* writing_usb_driver.rst: Enrich its ReST representationMauro Carvalho Chehab2017-04-111-100/+82
| | | | | | | | | | | | | | The pandoc conversion is not perfect. Do handwork in order to: - add a title to this chapter; - adjust function and struct references; - use monospaced fonts for C code names; - some other minor adjustments to make it better to read in text mode and in html. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* gadget.rst: Enrich its ReST representation and add kernel-doc tagMauro Carvalho Chehab2017-04-111-75/+52
| | | | | | | | | | | | | | | The pandoc conversion is not perfect. Do handwork in order to: - add a title to this chapter; - use the proper warning and note markups; - use kernel-doc to include Kernel header and c files; - remove legacy notes with regards to DocBook; - some other minor adjustments to make it better to read in text mode and in html. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* usb.rst: Enrich its ReST representationMauro Carvalho Chehab2017-04-111-31/+17
| | | | | | | | | | | | - use the proper warning and note markups; - add references for parts of the document that will be cross-referenced on other USB docs; - some minor adjustments to make it better to read in text mode and in html. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* docs-rst: convert usb docbooks to ReSTMauro Carvalho Chehab2017-04-115-0/+2379
As we're moving out of DocBook, let's convert the remaining USB docbooks to ReST. The transformation itself on this patch is a no-brainer conversion using pandoc via this script: Documentation/sphinx/tmplcvt Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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